1. The Field of the Invention
This invention relates to heat transfer and, more particularly, to novel systems and methods for heat transfer through flat heat pipes covering large areas with respect to their length.
2. The Background Art
Heat transfer is the mechanism by which refrigeration systems maintain a cool region within a hotter region. Heat transfer is also the mechanism by which energy is carried from points of generation such as furnaces and the like to areas to be heated, such as materials, space heating, or the like. Heat transfer is driven by a difference in temperature between a material at a comparatively higher temperature driving energy to a material (e.g., location or object) at a lower temperature to receive that energy. In all cases of heat transfer, the temperature difference between the high temperature region or object and the lower temperature region or object is a driving potential for the transfer of heat, whether linear or non-linear in effect.
Typically, heat transfer deals with the resistance to heat transfer through various materials, spaces, and so forth. The study of radiation, conduction, and convection seeks to identify the controlling parameters that govern the relationship between the temperature differences, heat transferred, material properties, distances, areas, and the like. Thus, in general, it is desirable to minimize the thermal resistance in order to maximize heat transfer from a region of higher temperature to a region of lower temperature. Similarly thermal resistance is to be maximized in order to minimize heat transfer. To the extent that thermal resistance is reduced, more heat may be transferred with a comparatively lesser temperature difference.
Electrical equipment has always required consideration of heat transfer to remove the heat generated by electrical resistance losses. Likewise, in systems such as satellites, spacecraft, and the like, the importance of maintaining low temperatures in certain equipment, such as sensors creating or recording images, and the like may require unique combinations of temperatures and thermal resistance.
Meanwhile, mechanical connections and distances required to remove heat may be substantial. Moreover, structural requirements for mechanical support may be substantial, requiring support against the ‘g-forces’ or acceleration forces of launch and other movements. In fact, heat transfer and mechanical support are often at odds, wherein what is good for one is poor for the other. The result is tradeoffs that poorly serve one or both.
Finally, space is not without traffic of particles and various objects, within a broad range of sizes, from dust to satellite to asteroid sizes. These may be either naturally occurring or man-made. Space junk, small meteoric objects, and other projectiles may penetrate a surface of a satellite, permanently disabling mechanical, fluid, electrical, and other systems contained therein.
Thus, it would be an advance in the art to develop a more effective heat transfer system, particularly one that would be adaptable to satellite use, having much lower weight than earthbound and previous satellite systems. It would be an advance to provide reduced thermal resistance, permitting temperature differentials less than are presently known in the art of satellite, and even less than those of many earthbound systems.
It would be a further advance in the art to create a comparatively strong structural support system, compared to prior art systems of equivalent weight in satellites and earthbound systems. It would be a further advance if such as system would support robust heat transfer, having comparatively better heat flux per degree of temperature differential than prior art satellite systems of comparable weight.
It would be a yet further advance to provide redundancy against failure in cases of mechanical damage, such as penetration by space debris or other objects. This could be significantly more valuable than earthbound systems, where such protection is not required at comparable weights to those of satellites.